Just weeks after a May 21 N**ew England Journal of Medicine article found that users of diabetes drug Avandia were 43 percent more likely to have heart attacks, GlaxoSmithKline -- the drug's manufacturer -- has published a large-scale clinical study involving more than 4,000 people.
They found that 29 Avandia users died from heart attacks or heart disease, compared to 35 taking other drugs. Glaxo called the results reassuring. But the study, again published in the NEJM, was accompanied by three critical editorials, and doctors have questioned its validity.
The problems: the study wasn't blind. Instead, doctors and patients in the study knew what they were taking. The control group received a combination of two drugs, metformin and sulphonylurea, that are believed to cause heart problems, while the other group received both those drugs and Avandia, making comparison difficult.
There's also a possibility that recipients of Avandia -- which raises cholesterol levels -- may have been on cholesterol-lowering drugs which could have camouflaged Avandia's risks. And, finally, the study didn't explain why a significant number of patients dropped out of the trial or conduct follow-ups on their health.
The bottom line? It's not clear yet, but as Emory University biostatistics chief Michael Kutner said, "'It's a leap of faith' for the company now to say that these results suggest the drug is safe."
Experts: Results from new Avandia study not reassuring [Associated Press]
Diabetes Drug Still Has Heart Risks, Doctors Warn [New York Times]
